Interactions with the environment

Environmental
archeology (sometimes referred to as historical ecology) addresses
how people lived in the past, the environment they faced, the resources
and opportunities it provided or denied them, and the economic strategies
by which they made a living in the world around them. Archeological
sites very rarely consist entirely of humanly produced remains or
artifacts. They also contain a vast range of ecofacts such as soils
and sediments that compose the site to the remains of animals and
plants. Four areas of environmental archeology and their related fields
are discussed below.

Zooarcheology

Zooarcheology
(also known as archeozoology) is the study of faunal (animal)
remains from archeological sites. These primarily consist of the surviving
hard parts of the body, e.g. bones, teeth and shell. Such remains
represent for the most part the food refuse of ancient populations,
although they may also reflect the use of animals for transportation,
decoration or household pets. Zooarcheology, together with other bioarcheological
disciplines, provides the archeologist with a more complete picture
of the kinds of animals and plants present at a site—whether these
organisms represent food remains, living entities that were part of
the surrounding environment, or organisms present after the site was
abandoned. Faunal and floral remains can shed light on way of life
of past populations and the kind of environment they inhabited. Although
zooarcheology provides information about the animals themselves and
uses biological methods, its final aim is to understand the environmental
context of past human cultures.

Paleobotany

Paleobotany,
also referred to as archeobotany,
is a branch of paleontology dealing with fossil plants. A subfield
of paleobotany is paleoethnobotany,
which analyzes and interprets plant remains from archeological sites
in order to understand the past interactions between human populations
and plants (Thomas 1998:325) Paleobotanists particularly study macroflora
(seeds), phytoliths
(plant microfossils composed of silica) and plant pollen. Paleontology
is the study of fossils—any trace of a past life form. Although wood,
bones, and shells are the most common fossils, under certain conditions
soft tissues, tracks and trails, and even coprolites (fossil feces)
fossilized. Paleontologists study these fossils to help reconstruct
the history of the earth and the life on it.

Archeologists
primarily work with artifacts and human remains. Paleontology does
not usually deal with artifacts made by humans. However, archeologists
and paleontologists might work together. For instance, a paleontologist
might identify fossil animal bones associated with an archeological
site to determine what the people who lived there ate; or a paleontologist
might analyze the climate at the time a particular archeological site
was inhabited.

Soil analysis

Soil analysis
can tell archeologists about the conditions in which it was formed,
the changes that have taken place since then, and, in some cases,
the activities of humans. Soils consist of an inorganic mix of rock
particles and minerals and organic material (humus) derived from decayed
plants (McIntosh 1999:105). Archeopedology
is the study of ancient soils in archeological contexts.
At archeological sites soils often retain matter from cultivated plants,
fires, human-made features
and human daily activities such as cooking or waste disposal.

Archeologists analyze soils in several ways. One method is soil or sediment color and texture
analysis. Determining each color in a soil layer is important because
archeologists want to see the transition between layers. A difference
in soil layer color can show age, use of site, activities, and eating habits. Archeologists
use a Munsell Color Chart to determine the color of a soil or sediment.
Each color is given a code of letters and numbers that can be compared
to those of other colors in the soil profile.

The chart has
sets of standardized color chips arranged in rows on several pages.
Archeologists obtain a code by comparing the soil color to one of
the pages in the book. The purpose of this system is to avoid arbitrary
color descriptions. Archeologists
may analyze soils microscopically. Magnification may reveal particles
that indicate the original function of archeological structures or
deposits. For example, minute pieces of charcoal suggest fires, while
phytoliths may determine the past presence of specific plants (McIntosh
1999:105).

Archeologists
may chemically analyze soils. Human activity can alter soil chemistry,
often enriching soils, particularly in their phosphorus or nitrogen
concentrations. Soil samples can be taken both within features as
well as at regularly spaced intervals throughout the site in an attempt
to find patterns
in chemical concentrations that indicate human activities such as
trash disposal or soil fertilization. Archeologists may test soils
in the field or send samples to laboratories for analysis (Hester
et al. 1997:136).

Geomorphology

Geomorphology
is the science
that studies
the general configuration of the Earth's surface, specifically the
study of the classification, description, nature, origin, and development
of present landforms and their relationships to underlying structures,
and of the history of geologic changes as recorded by these surface
features. Through geoarcheology,
archeologists incorporate geomorphological studies into their research
to gain an understanding of what earlier landforms were like and where
sites may be potentially located as well as insight regarding prehistoric
raw material choices, extraction technologies, mining economy, site
formation processes, and landscape history. Geoarcheologists often
use high-tech remote sensing techniques, such as ground penetrating
radar and seismic sensing.

Fun fact

1.8
billion years ago (long before people were around), the western
edge of the continent was located west of what is now Nevada's
Lake Mead National Recreation Area. Geologic
evidence of a collision between this coast and offshore
volcanic islands that occurred 1.7 billion years ago is visible
around Lake Mead.

Try it yourself

The
Mystery of the Stolen Artifacts
This
activity is a fictional trial of a man accused of illegally
taking Anasazi artifacts from public land. One piece of evidence
is genetic information from modern plant remains that were found
inside one of the pots. You review the evidence and decide whether
the man is guilty or innocent.